Answer:4
Step-by-step explanation:2x+y+z=2(-2)+3+5=(-4)+3+5=(-1)+5=4
Answer:
There are 45 2-point questions and 5 4-point questions
Step-by-step explanation:
Answer:

So then the correct answer is B. $200.
Step-by-step explanation:
Notation
Let X be the average contribution size before John makes his contribution.
Let Y be the total contribution size before John makes his contribution.
Let Z be John's contribution.
We know that for this case $ 75 represent the original average amount before the contribution with 50% increase so we can set up the following equation in order to find the original average amount

And solvong for X we got:

Now we can find the total contribution before the donation with the following proportion:


And then with the formula of average taking in count the 6 values we can find the size of donation Z like this:



So then the correct answer is B. $200.
let the unknown answer be equal to f
.-2.1 - f = -3/2
-f = -3/2 + 2.1
-f = 0.6
f = -0.6